DYNAMICS OF HYPORHEIC EXCHANGE AND HEAT TRANSPORT IN THE RIPARIAN ZONE IN RESPONSE TO DAM-INDUCED WATER FLUCTUATIONS

2017 ◽  
Author(s):  
Dongsheng Liu ◽  
Xiaobing Chen ◽  
Jian Zhao
Keyword(s):  
Heat Transport ◽  
Riparian Zone ◽  
Hyporheic Exchange

scholarly journals Feasible Ways Promoting Nitrate Removal in Riparian Zone Downstream of a Regulated River

Water ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 2054
Author(s):  
Dongsheng Liu ◽  
Bei Zhu ◽  
Haoyu Zhu ◽  
Jian Zhao
Keyword(s):  
Ecological Restoration ◽  
Riparian Zone ◽  
Nitrate Removal ◽  
Reaction Model ◽  
Regulated River ◽  
Hyporheic Exchange ◽  
Fixed Degree ◽  
Chemical Methods ◽  
Physical Methods ◽  
Contaminated Area

Set in the downstream riparian zone of Xin’an River Dam, this paper established a 2D transversal coupling flow and solute transport and reaction model by verification within situ groundwater level and temperature. The denitrifying methods and principles in the riparian zone from the perspective of hyporheic exchange were explored, which provided a basis for the engineering techniques for river ecological restoration. Our studies have shown that under the condition of water level fluctuation, a biological method such as adding denitrifying bacteria biomass to a fixed degree (the same below) can greatly increase the denitrifying rate (1.52 g/d) in the riparian zone; chemical methods such as adding organic carbon into the surface water or groundwater can increase the total riparian nitrate removal (8.00–8.18 g) and its efficiency (19.5–20.0%) to a great extent; hydrogeological methods such as silt cleaning of the aquifer surface or local pumping around the contaminated area can increase the total riparian nitrate removal (1.06–14.8 g) to some extent, but correspondingly reduce the denitrifying efficiency (0.95–1.4%); physical methods such as designing the bank form into gentle slope or concave shape can slightly increase the total riparian nitrate removal (0.22–0.52 g) and correspondingly improve the denitrifying efficiency (0.25–0.85%). At the application level of river ecological restoration, integrated adopting the above methods can make the riparian denitrifying effect “fast and good”.

Impact of dam operations on hyporheic exchange in the riparian zone of a regulated river

2009 ◽  
Vol 23 (15) ◽  
pp. 2129-2137 ◽  
Author(s):  
Audrey Hucks Sawyer ◽  
M. Bayani Cardenas ◽  
Ashleigh Bomar ◽  
Meredith Mackey
Keyword(s):  
Riparian Zone ◽  
Regulated River ◽  
Hyporheic Exchange

Using water temperature series and hydraulic heads to quantify hyporheic exchange in the riparian zone

2019 ◽  
Vol 27 (4) ◽  
pp. 1419-1437 ◽  
Author(s):  
Jie Ren ◽  
Wenbing Zhang ◽  
Jie Yang ◽  
Yinjun Zhou
Keyword(s):  
Water Temperature ◽  
Riparian Zone ◽  
Temperature Series ◽  
Hyporheic Exchange

Dynamic processes of hyporheic exchange and temperature distribution in the riparian zone in response to dam-induced water fluctuations

2018 ◽  
Vol 22 (3) ◽  
pp. 465-475 ◽  
Author(s):  
Dongsheng Liu ◽  
Jian Zhao ◽  
Xiaobing Chen ◽  
Yingyu Li ◽  
Shipan Weiyan ◽  
...  
Keyword(s):  
Temperature Distribution ◽  
Riparian Zone ◽  
Hyporheic Exchange ◽  
Dynamic Processes

scholarly journals Heat transport of diurnal temperature oscillations upon river-water infiltration investigated by fiber-optic high-resolution temperature profiling

2011 ◽  
Vol 8 (3) ◽  
pp. 6257-6289
Author(s):  
T. Vogt ◽  
M. Schirmer ◽  
O. A. Cirpka
Keyword(s):  
River Water ◽  
Heat Transport ◽  
Unsaturated Zone ◽  
Riparian Zone ◽  
Shallow Groundwater ◽  
Temporal Variations ◽  
Water Infiltration ◽  
Diurnal Temperature ◽  
Temperature Oscillations ◽  
Losing River

Abstract. River-water infiltration is of high relevance for hyporheic and riparian groundwater ecology as well as for drinking water supply by river-bank filtration. Heat has become a popular natural tracer to estimate exchange rates between rivers and groundwater. However, quantifying flow patterns and velocities is impeded by spatial and temporal variations of exchange fluxes, insufficient sensors spacing during field investigations, or simplifying assumptions for analysis or modeling such as uniform flow. The objective of this study is to investigate local heat transport upon river-water infiltration in the riverbed and the adjacent riparian zone of the losing River Thur in northeast Switzerland. Here we have applied distributed temperature sensing (DTS) along optical fibers wrapped around three tubes to measure high-resolution temperature profiles of the unsaturated zone and shallow groundwater. Diurnal temperature oscillations were tracked in the subsurface and analyzed by means of dynamic harmonic regression to extract amplitudes and phase angles. Subsequent calculations of amplitude attenuation and time shift relative to the river signal show in detail vertical and temporal variations of heat transport. In addition, we apply a numerical two-dimensional heat transport model for the unsaturated zone and shallow groundwater to get a better understanding of the observed heat transport processes in the riparian zone. Our results show that heat transfer of diurnal temperature oscillations from the losing river through groundwater is influenced by thermal exchange with the unsaturated zone. Neglecting the influence of the unsaturated zone would cause biased interpretation and underestimation of groundwater flow velocities. In addition, the observed riparian groundwater temperature distribution cannot be described by uniform flow, but rather by horizontal groundwater flow velocities varying over depth.

scholarly journals A Hydrothermal Coupling Model for Estimating Temperature Variations in the Riparian Zone

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Wenbing Zhang ◽  
Zhenzhong Shen ◽  
Jie Ren ◽  
Wanlin Zhang ◽  
Liqun Xu ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Prediction Models ◽  
Riparian Zone ◽  
Coupling Model ◽  
Hyporheic Exchange ◽  
Accurate Estimation ◽  
Model Parameters ◽  
Equivalent Thermal Conductivity ◽  
Temperature Variations ◽  
Temperature Changes

In research using heat tracing technology to investigate the lateral hyporheic exchange in the shallow geological body of the riparian zone, the accurate estimation of temperature changes can provide a scientific basis for quantifying the process of lateral hyporheic exchange. To improve the accuracy of estimating temperature changes in the riparian zone, a hydrothermal coupling model considering parameter heterogeneity was established based on existing models of the relationship between thermal conductivity and saturation. The model was verified by temperature data from laboratory experiments, and the effect of the thermal conductivity prediction models was compared with that of the partial differential equation (PDE) modeling approach. The results show that the established hydrothermal coupling model can effectively characterize the temperature changes observed in a generalized laboratory model of the riparian zone, and the model simulation effects vary with the equivalent thermal conductivity models. In addition, several thermal conductivity empirical models are suggested for further application. The model parameter sensitivity analysis indicated that the hydraulic conductivity ks, VG model parameters (α and β) and heat capacity of soil Cs have a relatively large effect on the temperature output of the model. The results of this study will provide reference for the selection of equivalent thermal conductivity model for simulating temperature variations in the riparian zone.

Causal heat transport induced by zeptosecond laser pulses

2002 ◽  
Vol 12 (3) ◽  
pp. 201-206 ◽  
Author(s):  
Janina Marciak-Kozłowska ◽  
Mirosław Kozłowski
Keyword(s):  
Heat Transport ◽  
Laser Pulses
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